Grinding wheel assembly

ABSTRACT

An abrasive article is disclosed and can include a core comprising a polymer material. The core can include an upper surface, an outer peripheral surface, an upper recessed portion extending into the core from the upper surface and a peripheral recess extending into the outer peripheral surface. The abrasive article can also include a bonded abrasive body disposed within the peripheral recess of the outer peripheral surface of the core and a cover plate having an upper surface. The cover plate can fit into the upper recessed portion of the upper surface the core so that the upper surface of the cover plate is substantially coplanar with the upper surface of the core.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority under 35 U.S.C. § 119(e) to U.S.Provisional Patent Application No. 62/671,534, entitled “GRINDING WHEELASSEMBLY”, by Cecile O. MEJEAN et al., filed May 15, 2018, which isassigned to the current assignees hereof and incorporated herein byreference in its entirety.

FIELD OF THE DISCLOSURE

The present invention relates, in general, to grinding wheels andmulti-piece grinding wheel assemblies.

BACKGROUND

Abrasive grinding wheels can be used to smooth and contour the edges ofcertain flat materials, e.g., sheets of glass, for safety and cosmeticreasons. Such abrasive grinding wheels may include diamond-containingabrasive wheels and may be used to shape the edges of materials forvarious industries, including but not limited to automotive,architectural, furniture, and appliance industries.

The industry continues to demand improved grinding wheel assemblies,particularly for applications of grinding the edges of flat materials.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure may be better understood, and its numerousfeatures and advantages made apparent to those skilled in the art byreferencing the accompanying drawings.

FIG. 1 includes an illustration of a side plan view of a grinding wheelassembly in accordance with an embodiment.

FIG. 2 includes an illustration of an exploded side plan view of agrinding wheel assembly in accordance with an embodiment.

FIG. 3 includes an illustration of a top plan view of an abrasivearticle for a grinding wheel assembly in accordance with an embodiment.

FIG. 4 includes an illustration of a bottom plan view of an abrasivearticle for a grinding wheel assembly in accordance with an embodiment.

FIG. 5 includes an illustration of a side plan view of an abrasivearticle for a grinding wheel assembly in accordance with an embodiment.

FIG. 6 includes an illustration of a side plan view of a core for anabrasive article for a grinding wheel assembly in accordance with anembodiment.

FIG. 7 includes an illustration of a cross-section view, taken alongLine 7-7 in FIG. 3, of an abrasive article for a grinding wheel assemblyin accordance with an embodiment.

FIG. 8 includes an illustration of a top plan view of a cover plate fora grinding wheel assembly in accordance with an embodiment.

FIG. 9 includes an illustration of a bottom plan view of a cover platefor a grinding wheel assembly in accordance with an embodiment.

FIG. 10 includes an illustration of a side plan view of a cover platefor a grinding wheel assembly in accordance with an embodiment.

FIG. 11 includes an illustration of a cross-section view, taken alongLine 11-11 in FIG. 8, of a cover plate for a grinding wheel assembly inaccordance with an embodiment.

FIG. 12 includes an illustration of a cross-section view of a coverplate fitted into an abrasive article for a grinding wheel assembly inaccordance with an embodiment.

FIG. 13 includes an illustration of a side plan view of a grinding wheelassembly in accordance with an embodiment.

FIG. 14 includes an illustration of an exploded side plan view of agrinding wheel assembly in accordance with an embodiment.

FIG. 15 includes an illustration of a top plan view of an abrasivearticle for a grinding wheel assembly in accordance with an embodiment.

FIG. 16 includes an illustration of a bottom plan view of an abrasivearticle for a grinding wheel assembly in accordance with an embodiment.

FIG. 17 includes an illustration of a side plan view of an abrasivearticle for a grinding wheel assembly in accordance with an embodiment.

FIG. 18 includes an illustration of a side plan view of a core for anabrasive article for a grinding wheel assembly in accordance with anembodiment.

FIG. 19 includes an illustration of a cross-section view, taken alongLine 19-19 in FIG. 15, of an abrasive article for a grinding wheelassembly in accordance with an embodiment.

FIG. 20 includes an illustration of a top plan view of a cover plate fora grinding wheel assembly in accordance with an embodiment.

FIG. 21 includes an illustration of a bottom plan view of a cover platefor a grinding wheel assembly in accordance with an embodiment.

FIG. 22 includes an illustration of a side plan view of a cover platefor a grinding wheel assembly in accordance with an embodiment.

FIG. 23 includes an illustration of a cross-section view, taken alongLine 23-23 in FIG. 20, of a cover plate for a grinding wheel assembly inaccordance with an embodiment.

FIG. 24 includes an illustration of a cross-section view of a coverplate fitted into an abrasive article for a grinding wheel assembly inaccordance with an embodiment.

DETAILED DESCRIPTION

The following is generally directed to grinding wheel assemblies thatare particularly suitable for grinding and smoothing the edges ofbrittle materials, such as glass.

Embodiments are directed to abrasive articles which may be in the formof grinding wheels. In one aspect, a grinding wheel assembly can includean abrasive body mounted in a head assembly that can be easily removedand replaced after the abrasive body is no longer providing sufficientabrasion during use. The grinding wheel assembly can include an arbor inwhich a pull stud can be installed. The arbor can further providesupport for an abrasive body. In one aspect, the arbor can include amounting plate and the abrasive body can be held between the mountingplate and a cover plate. The grinding wheel assembly can be particularsuitable for operations of grinding the edges of glass, such asautomobile glass and flat glass. Further, the grinding wheel assemblycan allow for relatively quicker removal and replacement of the abrasivearticle after the abrasive article is no longer useful. The pull stud,the arbor, and the cover plate need not be replaced after the abrasivebody is no longer useful.

Grinding Wheel Assembly

Referring initially to FIG. 1 through FIG. 2, a grinding wheel assemblyis illustrated and is generally designated 100. As shown, the grindingwheel assembly 100 can include a pull stud 102, an arbor 104, anabrasive article 106, a cover plate 108, and at least one fastener 110,e.g., a threaded fastener. A threaded fastener with a socket head isdepicted in the FIGs., but it is to be understood that any other type ofthreaded fastener may be used. For example, socket head cap screws maybe used. In particular, standard grade 12.9 M8 socket head cap screwsmay be used to fasten the cover plate to the arbor 104. Alternatively,standard grade 12.9 M10 socket head cap screws or standard grade 12.9M12 socket head cap screws may be used. FIG. 2 also indicates that threethreaded fasteners 110 can be used to mount the cover plate 108 and theabrasive article 106 to the arbor 104. However, in an alternativeembodiment, a single, centrally located threaded fastener can be used tomount the cover plate 108 and the abrasive article 106 to the arbor 104.In such a case, the single, centrally located threaded fastener can passthrough a center of the cover plate 108, a center of the abrasivearticle 106, and engage threads formed in the center of the arbor 104.

The pull stud 102, the arbor 104, and the cover plate 108 can include ametal or a metal alloy. For example, the metal can be stainless steel ortitanium. Further, the metal can include a hardened metal, such ashardened steel. It is to be understood that the material utilized forthe pull stud 102, the arbor 104, and the cover plate 108 will minimizewearing of these elements during use. The abrasive article 106, however,will wear during grinding operations performed on the edges of variousworkpieces. After the abrasive article 106 is sufficiently worn, theabrasive article 106 may be removed and replace with a new abrasivebody. Alternatively, the abrasive article 106 may be removed and theouter periphery of the abrasive article 106 may be reground. Thereafter,the abrasive article 106 may be reinstalled and used to perform furthergrinding operations.

Arbor

As shown in FIG. 2, the arbor 104 can include a body 200 that can definea proximal end 202 and a distal end 204. The body 200 of the arbor 104can include a generally frustoconical drive shaft 206 that can extendfrom the proximal end 202 of the body 200 to a central flange 208 thatextends outwardly from the body 130. Further, the body 200 of the arbor104 can include a mounting plate 210 that can extend radially outwardfrom the body 200 at, or near, the distal end 204 of the body 130 of thearbor 104. As illustrated, the mounting plate 210 can include at leastone threaded bore 212 radially offset from a central axis 214. The atleast one threaded bore 212 can be configured to receive the at leastone fastener 110. In a particular aspect, the arbor 104 can include acentral bore 216. The central bore can be formed with threads (notshown). Further, the central bore 216 of the arbor 104 can be configuredto threadably engage a portion of the pull stud 102 when it is insertedin the central bore 216 of the arbor 104.

Abrasive Article

Referring now to FIG. 3 through FIG. 7, details regarding the abrasivearticle 106 are shown. The abrasive article 106 can include a core 300that can include an upper surface 302, a lower surface 304, and an outerperipheral surface 306. In particular, as shown in FIG. 6, the abrasivearticle 106 can include a peripheral recess 308 formed in the outerperipheral surface 306 of the core 300. As shown, the peripheral recess308 can extend radially inwardly from the outer peripheral surface 304.

As further shown in FIG. 7, the core 300 of the abrasive article 106 canfurther include an upper recessed portion 310 that can extend inwardlyfrom the upper surface 302 of the core 300 along a central axis 312. Theupper recessed portion 310 can include a recessed surface 314 and asidewall 316. In a particular aspect, the upper recessed portion 310 canbe bound by the sidewall 316 and can extend between the upper surface302 and the recessed surface 314. In a particular aspect, the recessedsurface 314 can form an angle, α, with respect to the upper surface 302,or an axis or plane that is parallel to the upper surface 302. In aparticular aspect, α can be greater than or equal to 5°. In anotheraspect, a can be greater than or equal to 7.5°, such as greater than orequal to 10°, greater than or equal to 12.5°, or greater than or equalto 15°. In still another aspect, α can be less than or equal to 30°,such as less than or equal to 27.5°, less than or equal to 25°, lessthan or equal to 22.5°, or less than or equal to 22°.

FIG. 3, FIG. 4, and FIG. 7 indicate that the core 300 can furtherinclude a central bore 318. In a particular aspect, the central bore 318can be concentric with the central axis 312. Further, the central bore318 can extend from the upper recessed portion 310 to the lower surface304 of the core 300. In particular, the central bore 318 can extend fromthe recessed surface 314 of the upper recessed portion 310 to the lowersurface 304 of the core 300. The central bore 318 can be bound an innersurface 320 of the core 300.

As indicated in FIG. 3, the upper recessed portion 310, or the recessedsurface 314 of the upper recessed portion 310, can have a radial width,W_(RP), measured from the inner surface 320 of the core 300 to thesidewall 316 of the upper recessed portion 310. Further, the core 300can have a radial width, W_(C), measured from the inner surface 320 ofthe core 300 to the outer surface 306 of the core 300. In a particularaspect, W_(RP) can be greater than or equal to 40% W_(C). Further,W_(RP) can be greater than or equal to 45% W_(C), such as greater thanor equal to 50% W_(C), or greater than or equal to 55% W_(C). In anotheraspect, W_(RP) can be less than or equal to 75% W_(C), such as less thanor equal to 70% W_(C), less than or equal to 65% W_(C), or less than orequal to 60% W_(C).

FIG. 4 and FIG. 7 further indicate that the core 300 of the abrasivearticle 106 can also include a central mounting hub 322 thatcircumscribes, or surrounds, the central bore 318 formed in the core300. The central mounting hub 322 and the lower surface 304 of the core300 can abut, or engage, the mounting plate 210 on the arbor 104 whenthe abrasive article 106 is installed on the arbor 104 as illustrated inFIG. 1. The central mounting hub 322 can include a plurality of fastenerbores 324 equally spaced around the central axis 312. Each fastener bore324 can receive one of the fasteners 110 therethrough when the grindingwheel assembly 100 is assembled as shown in FIG. 1.

As shown in FIG. 3, FIG. 4, FIG. 5, and FIG. 7, the abrasive article 106can further include a bonded abrasive body 330 disposed within the core300. In particular, the bonded abrasive body 330 can be disposed withinthe peripheral recess 308 formed in the outer peripheral surface 306 ofthe core 300. In particular, the core 300 can be molded around theabrasive body 330 and the core 300 can include a plurality ofmanufacturing holes 332 that are formed by a tool configured to hold theabrasive body 330 within a mold during the molding process.

In a particular aspect, each manufacturing hole 332 can extends axiallyinto the core 300 in a direction parallel to the central axis 312.Further, each manufacturing hole 332 can at least partially radiallyoverlaps a portion of the bonded abrasive body 330. In a particularaspect, the core 300 can also include a plug (not shown) that can befitted into each manufacturing hole 332. Further, the core 300 caninclude at least two plugs (not shown) and each of the plugs can befitted into a respective manufacturing hole 332. Each of the at leasttwo plugs can be substantially identical. On the other hand, each of theat least two plugs can be different. For example, each of the at leasttwo plugs can have different densities. Moreover, each of the at leasttwo plugs can have different masses.

In a particular aspect, the core 300 may include a particular polymermaterial that facilitates improved performance of the bonded abrasivebody, including but not limited to, aspects of strength, wearability,vibration damping, and manufacturability.

In one embodiment, the core 300 of the abrasive article 106 of thepresent disclosure may have a particular heat deflection temperature(HDT) at 0.45 MPa of at least about 130° C., such as at least about 140°C., at least about 150° C., at least about 160° C., at least about 180°C., at least about 200° C.; at least about 230° C., at least about 250°C., or at least about 260° C. In another non-limiting embodiment, theHDT of the core at 0.45 MPa may not be not greater than 400° C., such asnot greater than 380° C., or not greater than 360° C. It will beappreciated that the HDT at 0.45 MPa of the core 300 can be within arange between any of the minimum and maximum values noted above, such asfrom about 130° C. to about 400° C., from about 200° C. to about 350°C., or from about 250° C. to about 330° C.

In another embodiment, the core 300 of the abrasive article 106 may havea shrinkage ratio of not greater than 3%, such as not greater than 2%,not greater than 1.5%, not 1.0%, not greater than 0.8%, not greater than0.5%, not greater than 0.3%, not greater than 0.1%, or not greater than0.05%. In a particular embodiment, the shrinkage ratio may be notgreater than 0.1%. In another embodiment, the shrinkage ratio of thecore 300 is at least 0.001% or at least 0.005%. It will be appreciatedthat the shrinkage ratio of the core 300 can be within a range betweenand including any of the minimum and maximum values noted above, such asfrom 0.001% to 3%, from 0.005% to 1%, or from 0.001% to 0.1%.

In a further embodiment, the core 300 of the abrasive article can have aCharpy impact of at least 45 kJ/m2, such as at least 50 kJ/m2, at least55 KJ/m2, at least 60 kJ/m2, at least 80 kJ/m2, at least 100 kJ/m2, orat least 150 kJ/m2; in another aspect, the Charpy impact may be notgreater than 300 kJ/m2 or not greater than 250 kJ/m2. It will beappreciated that the Charpy impact can be within a range from any of theminimum and maximum values noted above, such as from 45 kJ/m2 to 300kJ/m2, from 50 kJ/m2 to 250 kJ/m2, or from 100 KJ/m2 to 180 kJ/m2.

In one embodiment the core 300 can include a polymer material selectedfrom the group of a polyamide (PA), a polybutylene terephthalate (PBT),a polyphenylene sulfide (PPS), ethylene tetrafluoroethylene (ETFE), apolyetherketone (PEEK), a polyester (PE), a polyethyleneimine (PEI), apolyethersulfone (PESU), a polyethylene terephthalate (PET), apolyphthalamide (PPA), a poly (p-phenylene sulfide), a polycarbonate(PC), acrylonitrile-butadiene-styrene (ABS), PC-ABS, or any combinationthereof. In an aspect, the polymer material may be a nylon, a PBT, aPPS, or a PC-ABS. The nylon may be, for example, nylon 6, nylon 66,nylon 610, nylon 612, nylon 66/6, nylon 410, or nylon 46. In aparticular embodiment, the polymer material of the core 300 may consistessentially of PPS. In another particular embodiment, the polymermaterial of the core 300 may consist essentially of PC-ABS. In anotherembodiment, the polymer material of the core 300 may be essentially freeof nylon.

In another embodiment, the core 300 may further contain reinforcingfibers and/or a powder distributed within the polymer material. Thereinforcing fibers may include, for example, glass fibers, carbonfibers, ceramic fibers, organic fibers, mineral fibers, or combinationsthereof. Suitable powders may be, for example, calcium carbonate, glasspowder, mineral powder, or talc.

In a particular embodiment, the reinforcing fibers of the core 300 mayconsist essentially of carbon fibers. In another particular embodiment,the reinforcing fibers of the core 300 can consist essentially of glassfibers. Consisting essentially should be understood only one specifictype of fibers containing only unavoidable impurities.

The amount of reinforcing fibers and/or powder contained in the core 300may be at least about 1 wt %, such as at least about 5 wt %, at leastabout 10 wt %, at least about 15 wt %, at least about 20 wt %, at leastabout 25 wt %, or at least about 30 wt %, based on the total weight ofthe core. In another aspect, the amount of reinforcing fibers and/orpowder may be not greater than 60 wt %, such as not greater than 55 wt%, not greater than 50 wt %, not greater than 45 wt %, or not greaterthan 40 wt %. It will be appreciated that the amount of reinforcingfibers and/or powder contained in the core 300 can be within a rangebetween any of the minimum and maximum values noted above, such as fromabout 5 wt % to about 50 wt %, from about 15 wt % to about 40 wt %, fromabout 20 wt % to about 50 wt %, or from about 30 wt % to about 50 wt %based on the total weight of the core.

In one embodiment, the reinforcing fibers can have an average aspectratio of length to width of at least about 3, such as at least about 5,at least about 10, at least about 30, at least about 50, at least about100, at least about 500, or at least about 800. In another embodimentthe primary aspect ratio of the reinforcing fibers may be not greaterthan 5000, such as not greater than 3500, not greater than 2000, notgreater than 1200, not greater than 1100, or not greater than 1000. Itwill be appreciated that the average aspect ratio of the reinforcingfibers can be within a range between any of the minimum and maximumvalues note above, such as from about 3 to about 5000, from about 3 toabout 1300, from about 10 to about 1200, from about 100 to about 1200,from about 500 to about 1200, from about 700 to 1200, or from about 800to about 1200.

In one embodiment, the core 300 of the abrasive article 106 of thepresent disclosure may consist essentially of the polymer material andthe reinforcing fibers, the reinforcing fibers being present in anamount of 30 to 50 wt % based on the total weight of the core and havingan average aspect ratio of length to width of 500 to 1200.

In a particular embodiment, the core 300 may comprise PPS and carbonfibers, the carbon fibers having an average aspect ratio from about 800to about 1200, wherein the core can have a shrinkage ratio of notgreater than 0.1% and a tensile modulus of at least about 20.0 GPa.

In another particular embodiment, the core 300 can comprise PC-ABS andglass fibers, the glass fibers having an average aspect ratio from about800 to about 1200, wherein the core can have a shrinkage ratio of notgreater than 0.1% and a tensile modulus of at least about 20.0 GPa.

According to one embodiment, the core 300 of the abrasive article canrepresent a majority of the total volume of the abrasive article. Forexample, in one embodiment, the core 300 can be at least about 60 vol %based on the total volume of the abrasive article, such as at leastabout 70 vol %, at least about 75 vol %, at least 80 vol % or at least85 vol %. Still, in another non-limiting embodiment, the core 300 may benot greater than about 99 vol % of the abrasive article, such as at notgreater than about 97 vol %, not greater than about 95 vol %, or notgreater than about 90 vol %. It will be appreciated that the volumepercentage of the core 300 of the abrasive article based on the totalvolume of the abrasive article can be within a range between any of theminimum and maximum values noted above, such as from about 65 vol % toabout 99 vol %, from about 70° vol % to about 95 vol %, or from about 80vol % to about 95 vol %.

The bonded abrasive body 330 can be disposed in the 306 recess at theperipheral surface 304 of the core 300 and can include abrasiveparticles fixed in a bond material. Suitable abrasive particles caninclude, for example, oxides, carbides, nitrides, borides, diamond,cubic boron nitride, silicon carbide, boron carbide, alumina, siliconnitride, tungsten carbide, zirconia, or a combination thereof. In aparticular aspect, the abrasive particles of the bonded abrasive body330 are diamond particles. In at least one embodiment, the abrasiveparticles can consist essentially of diamond.

The abrasive particles contained in the bonded abrasive body 330 canhave an average particle size suitable to facilitate particular grindingperformance. For example, the abrasive particles can have a size lessthan about 2000 μm, such as less than about 1000 μm, less than about 500μm, or less than about 300 μm. In another aspect, the abrasive particlescan have a size of at least 0.01 μm, such as at least 0.1 μm, at leastabout 1 μm, at least 5 μm or at least 10 μm. It will be appreciated thatthe size of the abrasive particles contained in the bonded abrasive body330 can be within a range between any of the minimum and maximum valuesnoted above, such as from about 0.01 μm to about 2000 μm, from about 1μm to about 500 μm, from about 5 μm to about 300 μm or from about 50 μmto about 150 μm.

The bond material of the bonded abrasive body 330 an include aninorganic material, an organic material, and a combination thereof.Suitable inorganic materials for the use as bond material may includemetals, glass, glass-ceramics, and a combination thereof. For example,an inorganic bond material can include one or more metal compositions orelements such as Cu, Sn, Fe, W, WC, Co, and a combination thereof.Organic materials may include resins, for example thermosets,thermoplastics, and a combination thereof. For example, some suitableresins can include phenolic resins, epoxies, polyesters, cyanate esters,shellacs, polyurethanes, rubber, polyimides and a combination thereof.

The abrasive article 106 of the present disclosure may be selected froma range of suitable sizes to facilitate efficient grinding dependingupon the workpiece. In one embodiment, the abrasive article 106 caninclude an abrasive wheel having a diameter of at least about 25 mm,such as at least about 30 mm or at least about 50 mm. In anotherembodiment, the wheel diameter may be not greater than 500 mm, such asnot greater than 450 mm, not greater than 300 mm or not greater than 200mm. It will be appreciated that the wheel diameter can be within a rangebetween any of the minimum and maximum values noted above, such as fromabout 25 mm to about 500 mm, from about 50 mm to about 250 mm, or fromabout 25 mm to about 150 mm.

As illustrated in FIG. 5, the abrasive body 330 of the abrasive article106 can have an outer peripheral surface 334 that may have a profileground therein. As shown, the profile may be concave, or U-shaped.However, in other aspects, the profile may be angular, or V-shaped. Theprofile of the outer peripheral surface 334 of the abrasive body 330 ofthe abrasive article 106 will be reproduced in reverse on the materialto be shaped by the grinding wheel assembly 100.

The abrasive article 106 of the present disclosure may be selected froma range of suitable sizes to facilitate efficient grinding dependingupon the workpiece. In one embodiment, the abrasive article 106 caninclude a diameter of at least about 25 mm, such as at least about 30 mmor at least about 50 mm. In another embodiment, the diameter may be notgreater than 500 mm, such as not greater than 450 mm, not greater than300 mm or not greater than 200 mm. It will be appreciated that thediameter can be within a range between any of the minimum and maximumvalues noted above, such as from about 25 mm to about 500 mm, from about50 mm to about 250 mm, or from about 25 mm to about 150 mm.

The abrasive article 106 of the present disclosure can be designed forshaping the edges of a workpiece. The workpiece can be an inorganic ororganic material, such as, for example, glass, plastic, ceramic, ormetal. In a particular embodiment, the workpiece can include glass,including but not limited to automotive glass, architectural glass,furniture glass, optical glass, and glass used in displays and/or tocover electronic devices (e.g., a phone). The workpiece can further becrystalline, such as monocrystalline or polycrystalline, including butnot limited to sapphire.

In a particular embodiment, the abrasive article 106 of the presentdisclosure can be an abrasive wheel. In one aspect, the burst strengthof the abrasive wheel may be at least 135 m/s, such as at least 150 m/s,at least 160 m/s or at least 180 m/s. In another embodiment, the burststrength may be not larger than 300 m/s, such as not larger than 280m/s, or not larger than 250 m/s.

Cover Plate

FIG. 8 through FIG. 11 illustrate the details concerning theconstruction of the cover plate 108. The cover plate 108 can include abody 800 that is generally disk-shaped. Further, the body 800 of thecover plate 108 can include an upper surface 802 and a lower surface804. The body 800 of the cover plate 108 can also include an outer wall806 extending between the upper surface 802 and the lower surface 804.The lower surface 804 and outer wall 806 of the cover plate 108 areconfigured to be complimentary in size and shape to the recessed surface314 and the sidewall 316 of the core 300 of the abrasive article 106. Asdepicted in FIG. 12, this shape allows the cover plate 108 to fit intothe upper recessed portion 310 of the core 300 of the abrasive article106 and engage the recessed surface 314 and the sidewall 316.Specifically, the lower surface 804 of the body 800 of the cover plate108 can abut and engage the recessed surface 314 of the upper recessedportion 310 of the core 300 of the abrasive article 106. Moreover, theouter wall 806 of the body 800 of the cover plate 108 can abut andengage the sidewall 316 of the core 300 of the abrasive article 106 thesurrounds, or circumscribes, the recessed surface 314 of the upperrecessed portion 310 of the core 300 of the abrasive article 106.Accordingly, the upper recessed portion 310 of the core 300 of theabrasive article 106 is sized and shaped to receive the complimentarysized and shaped cover plate 108 therein. Further, the cover plate 108fits into the upper recessed portion 310 of the upper surface 302 of thecore 300 of the abrasive article 106, so that the upper surface 802 ofthe cover plate 108, i.e., the body 800 of the cover plate 108, issubstantially coplanar with the upper surface 302 of the core 300 of theabrasive article 106.

As illustrated in FIG. 10 and FIG. 11, a generally cylindrical hub 808can extend outwardly from the lower surface 804 of the body 800 of thecover plate 108 along a central axis 810. The cylindrical hub 808 isconfigured to extend into the central bore 318 of the core 300 of theabrasive article 106 when the cover plate 108 is fitted into the upperrecessed portion 310 of the core 300 of the abrasive article 106.Moreover, FIG. 12 shows that the central bore 318 of the core 300 of theabrasive article 106 can have a bore depth, D_(B), and the cover plate108, i.e., the cylindrical hug 808 of the body 800 of the cover plate108, can extend at least partially into the central bore 318 at a depth,D_(E), and D_(E) can be less than or equal to 50% D_(B). In anotheraspect, D_(E) can be less than or equal to 45% D_(B), such as less thanor equal to 40% D_(B), less than or equal to 35% D_(B), less than orequal to 30% D_(B), less than or equal to 25% D_(B), less than or equalto 20% D_(B), or less than or equal to 15% D_(B). In another aspect,D_(E) can be greater than or equal to 2.5% D_(B), such as greater thanor equal to 5% D_(B), greater than or equal to 7.5% D_(B), or greaterthan or equal to 10% D_(B). It is to be understood that D_(E) can bewithin a range between, and including, any of the maximum and minimumvalues of D_(E) described herein.

In a particular aspect, the cover plate 108, i.e., the body 800 of thecover plate 108, has a diameter, D_(CP), and W_(RP) of the core 300 ofthe abrasive article 106 can be greater than or equal to 10% D_(CP).Moreover, W_(RP) can be greater than or equal to 12.5% D_(CP), such asgreater than or equal to 15% D_(CP), greater than or equal to 17.5%D_(CP), or greater than or equal to 20% D_(CP). In another aspect,W_(RP) can be less than or equal to 30.0% D_(CP), such as less than orequal to 27.5% D_(CP), less than or equal to 25% D_(CP), or less than orequal to 22.5% D_(CP). It is to be understood that W_(RP) can be withina range between and including any of the maximum and minimum % D_(CP)values described herein.

In still another aspect, the upper recessed portion 310, or the recessedsurface 314 of the upper recessed portion 310, can have a surface area,A_(RP). Further, the cover plate 310, e.g., the upper surface 302 of thebody 300 of the cover plate, can have a surface area, A_(CP), and A_(RP)can less than or equal to 75.0% A_(CP). In another aspect, A_(RP) can beless than or equal to 72.5% A_(CP), such as less than or equal to 70.0%A_(CP), less than or equal to 67.5% A_(CP), less than or equal to 65.0%Au), less than or equal to 62.5% A_(CP), less than or equal to 60.0%A_(CP), or less than or equal to 57.5% A_(CP). In yet another aspect,A_(RP) can be greater than or equal to 40.0% A_(CP), such as greaterthan or equal to 42.5% A_(CP), greater than or equal to 45.0% A_(CP),greater than or equal to 47.5% A_(CP), greater than or equal to 50.0%A_(CP), greater than or equal to 52.5% A_(CP), or greater than or equalto 55.0% A_(CP). It is to be understood that A_(RP) can be within arange between and including any of the maximum and minimum % A_(CP)values described herein.

In another aspect, the core 300 of the abrasive article 106 can have aninternal volume, V_(C), that is the combined volume of the upperrecessed portion 310 of the core 300 of the abrasive article 106 and thecentral bore 318 of the core 300 of the abrasive article 106. It is tobe understood that V_(C) is the volume within the core 300 of theabrasive article 106, i.e., between the upper surface 302 of the core300 and the lower surface 304 of the core 300, that is bound by thesidewall 316 of the upper recessed portion 310 of the core 300, therecessed surface 314 of the upper recessed portion 310 of the core 300,and the inner wall 320 of the core 300. Further, a displaced volume,V_(D), which is the volume displaced, or filled, by the body 800 of thecover plate 108 when the cover plate 108 is installed within theabrasive article 106, e.g. within the upper recessed portion 310 and thecentral bore 318 of the core 300, can be greater than or equal to 60.0%V_(C). In another aspect, V_(D) can be greater than or equal to 62.5%V_(C), such as greater than or equal to 65.0% V_(C), greater than orequal to 67.5% V_(C), greater than or equal to 70.0% V_(C), greater thanor equal to 72.5% V_(C), greater than or equal to 75.0% V_(C), greaterthan or equal to 77.5% V_(C), greater than or equal to 80.0% V_(C), orgreater than or equal to 82.5% V_(C). In another aspect, V_(D) can beless than or equal to 100.0% V_(C), such as less than or equal to 97.5%V_(C), less than or equal to 95.0% V_(C), less than or equal to 92.5%V_(C), less than or equal to 90.0% V_(C), less than or equal to 87.5%V_(C), or less than or equal to 85.0% V_(C). It is to be understood thatV_(D) can be within a range between, and including, any of the minimumand maximum values of V_(D) described herein.

As shown in FIG. 8, FIG. 9, FIG. 11, and FIG. 12, the body 800 of thecover plate 108 can include at least one bore 812 extending through thecover plate 108, i.e., between the upper surface 802 and the lowersurface 804. The at least one bore 812 can be radially offset from thecentral axis 810. The at least one bore 812 can be a smooth walled boreand may be sized and shaped to allow the at least one fastener 110,shown in FIG. 1, to extend through the at least one bore 812 and engagethe at least one bore 812 in a slip fit arrangement. Further, the body800 of the cover plate 108 can include at least one generallysemi-circular cutout 814 that can be aligned with a manufacturing hole332 on the core 300 of the abrasive article 106 when the cover plate 108is installed within the abrasive article 106 as shown in FIG. 12.

In a particular embodiment, the cover plate 108 can be made from ametal, a metal alloy, or a combination thereof. Further, the cover plate108 can be from a non-ferrous metal. For example, the cover plate 108can be made from aluminum, an aluminum alloy, or a combination thereof.Moreover, the cover plate 108 can be made from copper, brass, or acombination thereof. Further still, the cover plate 108 can be made fromtin, bronze, or a combination thereof.

Grinding Wheel Assembly

Referring initially to FIG. 13 through FIG. 14, a grinding wheelassembly is illustrated and is generally designated 1300. As shown, thegrinding wheel assembly 1300 can include a pull stud 1302, an arbor1304, an abrasive article 1306, a cover plate 1308, and at least onefastener 1310, e.g., a threaded fastener. As shown, the threadedfasteners 1310 can include countersunk socket fasteners that will notextend beyond an upper surface of the cover plate 1308 or abrasivearticle 1306 when installed and assembled as shown in FIG. 13. FIG. 14indicates that three threaded fasteners 1310 can be used to mount thecover plate 1308 and the abrasive article 1306 to the arbor 1304.However, in an alternative embodiment, a single, centrally locatedthreaded fastener can be used to mount the cover plate 1308 and theabrasive article 1306 to the arbor 1304. In such a case, the single,centrally located threaded fastener can pass through a center of thecover plate 1308, a center of the abrasive article 1306, and engagethreads formed in the center of the arbor 1304.

The pull stud 1302, the arbor 1304, and the cover plate 1308 can includea metal or a metal alloy. For example, the metal can be stainless steelor titanium. Further, the metal can include a hardened metal, such ashardened steel. It is to be understood that the material utilized forthe pull stud 1302, the arbor 1304, and the cover plate 1308 willminimize wearing of these elements during use. The abrasive article1306, however, will wear during grinding operations performed on theedges of various workpieces. After the abrasive article 1306 issufficiently worn, the abrasive article 1306 may be removed and replacewith a new abrasive body. Alternatively, the abrasive article 1306 maybe removed and the outer periphery of the abrasive article 1306 may bereground. Thereafter, the abrasive article 1306 may be reinstalled andused to perform further grinding operations.

Arbor

As shown in FIG. 14, the arbor 1304 can include a body 1400 that candefine a proximal end 1402 and a distal end 1404. The body 1400 of thearbor 1304 can include a generally frustoconical drive shaft 1406 thatcan extend from the proximal end 1402 of the body 1400 to a centralflange 1408 that extends outwardly from the body 1330. Further, the body1400 of the arbor 1304 can include a mounting plate 1410 that can extendradially outward from the body 1400 at, or near, the distal end 1404 ofthe body 1330 of the arbor 1304. As illustrated, the mounting plate 1410can include at least one threaded bore 1412 radially offset from acentral axis 1414. The at least one threaded bore 1412 can be configuredto receive the at least one fastener 1310. In a particular aspect, thearbor 1304 can include a central bore 1416. The central bore can beformed with threads (not shown). Further, the central bore 1416 of thearbor 1304 can be configured to threadably engage a portion of the pullstud 1302 when it is inserted in the central bore 1416 of the arbor1304.

Abrasive Article

Referring now to FIG. 15 through FIG. 19, details regarding the abrasivearticle 1306 are shown. The abrasive article 1306 can include a core1500 that can include an upper surface 1502, a lower surface 1504, andan outer peripheral surface 1506. In particular, as shown in FIG. 18,the abrasive article 1506 can include a peripheral recess 1508 formed inthe outer peripheral surface 1506 of the core 1500. As shown, theperipheral recess 1508 can extend radially inwardly from the outerperipheral surface 1504.

As further shown in FIG. 19, the core 1500 of the abrasive article 1506can further include an upper recessed portion 1510 that can extendinwardly from the upper surface 1502 of the core 1500 along a centralaxis 1512. The upper recessed portion 1510 can include a recessedsurface 1514 and a sidewall 1516. In a particular aspect, the upperrecessed portion 1510 can be bound by the sidewall 1516 and can extendbetween the upper surface 1502 and the recessed surface 1514. In aparticular aspect, the recessed surface 1514 is substantially parallelto the upper surface 1502.

FIG. 15, FIG. 16, and FIG. 19 indicate that the core 1500 can furtherinclude a central bore 1518. In a particular aspect, the central bore1518 can be concentric with the central axis 1512. Further, the centralbore 1518 can extend from the upper recessed portion 1510 to the lowersurface 1504 of the core 1500. In particular, the central bore 1518 canextend from the recessed surface 1514 of the upper recessed portion 1510to the lower surface 1504 of the core 1500. The central bore 1518 can bebound an inner surface 1520 of the core 1500.

As indicated in FIG. 15, the upper recessed portion 1510, or therecessed surface 1514 of the upper recessed portion 1510, can have aradial width, W_(RP), measured from the inner surface 1520 of the core1500 to the sidewall 1516 of the upper recessed portion 1510. Further,the core 1500 can have a radial width, W_(C), measured from the innersurface 1520 of the core 1500 to the outer surface 1506 of the core1500. In a particular aspect, W_(RP) can be greater than or equal to 40%W_(C). Further, W_(RP) can be greater than or equal to 45% W_(C), suchas greater than or equal to 50% W_(C), or greater than or equal to 55%W_(C). In another aspect, W_(RP) can be less than or equal to 75% W_(C),such as less than or equal to 70% W_(C), less than or equal to 65%W_(C), or less than or equal to 60% W_(C).

FIG. 16 and FIG. 19 further indicate that the core 1500 of the abrasivearticle 1506 can also include a central mounting hub 1522 thatcircumscribes, or surrounds, the central bore 1518 formed in the core1500. The central mounting hub 1522 and the lower surface 1504 of thecore 1500 can abut, or engage, the mounting plate 210 on the arbor 1504when the abrasive article 1506 is installed on the arbor 1304 asillustrated in FIG. 13. The central mounting hub 1522 can include aplurality of fastener bores 1524 equally spaced around the central axis1512. Each fastener bore 1524 can receive one of the fasteners 1310therethrough when the grinding wheel assembly 1300 is assembled as shownin FIG. 13.

As shown in FIG. 15, FIG. 16, FIG. 17, and FIG. 19, the abrasive article1306 can further include a bonded abrasive body 1530 disposed within thecore 1500. In particular, the bonded abrasive body 1530 can be disposedwithin the peripheral recess 1508 formed in the outer peripheral surface1506 of the core 1500. In particular, the core 1500 can be molded aroundthe abrasive body 1530 and the core 1500 can include a plurality ofmanufacturing holes 1532 that are formed by a tool configured to holdthe abrasive body 1530 within a mold during the molding process.

In a particular aspect, each manufacturing hole 1532 can extends axiallyinto the core 1500 in a direction parallel to the central axis 1512.Further, each manufacturing hole 1532 can at least partially radiallyoverlaps a portion of the bonded abrasive body 1530. In a particularaspect, the core 1500 can also include a plug (not shown) that can befitted into each manufacturing hole 1532. Further, the core 1500 caninclude at least two plugs (not shown) and each of the plugs can befitted into a respective manufacturing hole 1532. Each of the at leasttwo plugs can be substantially identical. On the other hand, each of theat least two plugs can be different. For example, each of the at leasttwo plugs can have different densities. Moreover, each of the at leasttwo plugs can have different masses.

In a particular aspect, the core 1500 may include a particular polymermaterial that facilitates improved performance of the bonded abrasivebody, including but not limited to, aspects of strength, wearability,vibration damping, and manufacturability.

In one embodiment, the core 1500 of the abrasive article 1506 of thepresent disclosure may have a particular heat deflection temperature(HDT) at 0.45 MPa of at least about 130° C., such as at least about 140°C., at least about 150° C., at least about 160° C., at least about 180°C., at least about 200° C.; at least about 230° C., at least about 250°C., or at least about 260° C. In another non-limiting embodiment, theHDT of the core at 0.45 MPa may not be not greater than 400° C., such asnot greater than 380° C., or not greater than 360° C. It will beappreciated that the HDT at 0.45 MPa of the core 1500 can be within arange between any of the minimum and maximum values noted above, such asfrom about 130° C. to about 400° C., from about 200° C. to about 350°C., or from about 250° C. to about 330° C.

In another embodiment, the core 1500 of the abrasive article 1306 mayhave a shrinkage ratio of not greater than 3%, such as not greater than2%, not greater than 1.5%, not 1.0%, not greater than 0.8%, not greaterthan 0.5%, not greater than 0.3%, not greater than 0.1%, or not greaterthan 0.05%. In a particular embodiment, the shrinkage ratio may be notgreater than 0.1%. In another embodiment, the shrinkage ratio of thecore 1500 is at least 0.001% or at least 0.005%. It will be appreciatedthat the shrinkage ratio of the core 1500 can be within a range betweenand including any of the minimum and maximum values noted above, such asfrom 0.001% to 3%, from 0.005% to 1%, or from 0.001% to 0.1%.

In a further embodiment, the core 1500 of the abrasive article can havea Charpy impact of at least 45 kJ/m2, such as at least 50 kJ/m2, atleast 55 KJ/m2, at least 60 kJ/m2, at least 80 kJ/m2, at least 100kJ/m2, or at least 150 kJ/m2; in another aspect, the Charpy impact maybe not greater than 300 kJ/m2 or not greater than 250 kJ/m2. It will beappreciated that the Charpy impact can be within a range from any of theminimum and maximum values noted above, such as from 45 kJ/m2 to 300kJ/m2, from 50 kJ/m2 to 250 kJ/m2, or from 100 KJ/m2 to 180 kJ/m2.

In one embodiment the core 1500 can include a polymer material selectedfrom the group of a polyamide (PA), a polybutylene terephthalate (PBT),a polyphenylene sulfide (PPS), ethylene tetrafluoroethylene (ETFE), apolyetherketone (PEEK), a polyester (PE), a polyethyleneimine (PEI), apolyethersulfone (PESU), a polyethylene terephthalate (PET), apolyphthalamide (PPA), a poly (p-phenylene sulfide), a polycarbonate(PC), acrylonitrile-butadiene-styrene (ABS), PC-ABS, or any combinationthereof. In an aspect, the polymer material may be a nylon, a PBT, aPPS, or a PC-ABS. The nylon may be, for example, nylon 6, nylon 66,nylon 610, nylon 612, nylon 66/6, nylon 410, or nylon 46. In aparticular embodiment, the polymer material of the core 1500 may consistessentially of PPS. In another particular embodiment, the polymermaterial of the core 1500 may consist essentially of PC-ABS. In anotherembodiment, the polymer material of the core 1500 may be essentiallyfree of nylon.

In another embodiment, the core 1500 may further contain reinforcingfibers and/or a powder distributed within the polymer material. Thereinforcing fibers may include, for example, glass fibers, carbonfibers, ceramic fibers, organic fibers, mineral fibers, or combinationsthereof. Suitable powders may be, for example, calcium carbonate, glasspowder, mineral powder, or talc.

In a particular embodiment, the reinforcing fibers of the core 1500 mayconsist essentially of carbon fibers. In another particular embodiment,the reinforcing fibers of the core 1500 can consist essentially of glassfibers. Consisting essentially should be understood only one specifictype of fibers containing only unavoidable impurities.

The amount of reinforcing fibers and/or powder contained in the core1500 may be at least about 1 wt %, such as at least about 5 wt %, atleast about 10 wt %, at least about 15 wt %, at least about 20 wt %, atleast about 25 wt %, or at least about 30 wt %, based on the totalweight of the core. In another aspect, the amount of reinforcing fibersand/or powder may be not greater than 60 wt %, such as not greater than55 wt %, not greater than 50 wt %, not greater than 45 wt %, or notgreater than 40 wt %. It will be appreciated that the amount ofreinforcing fibers and/or powder contained in the core 1500 can bewithin a range between any of the minimum and maximum values notedabove, such as from about 5 wt % to about 50 wt %, from about 15 wt % toabout 40 wt %, from about 20 wt % to about 50 wt %, or from about 30 wt% to about 50 wt % based on the total weight of the core.

In one embodiment, the reinforcing fibers can have an average aspectratio of length to width of at least about 3, such as at least about 5,at least about 10, at least about 30, at least about 50, at least about100, at least about 500, or at least about 800. In another embodimentthe primary aspect ratio of the reinforcing fibers may be not greaterthan 5000, such as not greater than 3500, not greater than 2000, notgreater than 1200, not greater than 1100, or not greater than 1000. Itwill be appreciated that the average aspect ratio of the reinforcingfibers can be within a range between any of the minimum and maximumvalues note above, such as from about 3 to about 5000, from about 3 toabout 1300, from about 10 to about 1200, from about 100 to about 1200,from about 500 to about 1200, from about 700 to 1200, or from about 2000to about 1200.

In one embodiment, the core 1500 of the abrasive article 1306 of thepresent disclosure may consist essentially of the polymer material andthe reinforcing fibers, the reinforcing fibers being present in anamount of 30 to 50 wt % based on the total weight of the core and havingan average aspect ratio of length to width of 500 to 13200.

In a particular embodiment, the core 1500 may comprise PPS and carbonfibers, the carbon fibers having an average aspect ratio from about 800to about 1200, wherein the core can have a shrinkage ratio of notgreater than 0.1% and a tensile modulus of at least about 20.0 GPa.

In another particular embodiment, the core 1500 can comprise PC-ABS andglass fibers, the glass fibers having an average aspect ratio from about800 to about 1200, wherein the core can have a shrinkage ratio of notgreater than 0.1% and a tensile modulus of at least about 20.0 GPa.

According to one embodiment, the core 1500 of the abrasive article canrepresent a majority of the total volume of the abrasive article. Forexample, in one embodiment, the core 1500 can be at least about 60 vol %based on the total volume of the abrasive article, such as at leastabout 70 vol %, at least about 75 vol %, at least 80 vol % or at least85 vol %. Still, in another non-limiting embodiment, the core 1500 maybe not greater than about 99 vol % of the abrasive article, such as atnot greater than about 97 vol %, not greater than about 95 vol %, or notgreater than about 90 vol %. It will be appreciated that the volumepercentage of the core 1500 of the abrasive article based on the totalvolume of the abrasive article can be within a range between any of theminimum and maximum values noted above, such as from about 65 vol % toabout 99 vol %, from about 70° vol % to about 95 vol %, or from about 80vol % to about 95 vol %.

The bonded abrasive body 1530 can be disposed in the 1506 recess at theperipheral surface 1504 of the core 1500 and can include abrasiveparticles fixed in a bond material. Suitable abrasive particles caninclude, for example, oxides, carbides, nitrides, borides, diamond,cubic boron nitride, silicon carbide, boron carbide, alumina, siliconnitride, tungsten carbide, zirconia, or a combination thereof. In aparticular aspect, the abrasive particles of the bonded abrasive body1530 are diamond particles. In at least one embodiment, the abrasiveparticles can consist essentially of diamond.

The abrasive particles contained in the bonded abrasive body 1530 canhave an average particle size suitable to facilitate particular grindingperformance. For example, the abrasive particles can have a size lessthan about 2000 μm, such as less than about 1000 μm, less than about 500μm, or less than about 300 μm. In another aspect, the abrasive particlescan have a size of at least 0.01 μm, such as at least 0.1 μm, at leastabout 1 μm, at least 5 μm or at least 10 μm. It will be appreciated thatthe size of the abrasive particles contained in the bonded abrasive body1330 can be within a range between any of the minimum and maximum valuesnoted above, such as from about 0.01 μm to about 2000 μm, from about 1μm to about 500 μm, from about 5 μm to about 300 μm or from about 50 μmto about 150 μm.

The bond material of the bonded abrasive body 1530 an include aninorganic material, an organic material, and a combination thereof.Suitable inorganic materials for the use as bond material may includemetals, glass, glass-ceramics, and a combination thereof. For example,an inorganic bond material can include one or more metal compositions orelements such as Cu, Sn, Fe, W, WC, Co, and a combination thereof.Organic materials may include resins, for example thermosets,thermoplastics, and a combination thereof. For example, some suitableresins can include phenolic resins, epoxies, polyesters, cyanate esters,shellacs, polyurethanes, rubber, polyimides and a combination thereof.

The abrasive article 1306 of the present disclosure may be selected froma range of suitable sizes to facilitate efficient grinding dependingupon the workpiece. In one embodiment, the abrasive article 1306 caninclude an abrasive wheel having a diameter of at least about 25 mm,such as at least about 30 mm or at least about 50 mm. In anotherembodiment, the wheel diameter may be not greater than 500 mm, such asnot greater than 450 mm, not greater than 300 mm or not greater than 200mm. It will be appreciated that the wheel diameter can be within a rangebetween any of the minimum and maximum values noted above, such as fromabout 25 mm to about 500 mm, from about 50 mm to about 250 mm, or fromabout 25 mm to about 150 mm.

As illustrated in FIG. 17, the abrasive body 1530 of the abrasivearticle 1306 can have an outer peripheral surface 1534 that may have aprofile ground therein. As shown, the profile may be concave, orU-shaped. However, in other aspects, the profile may be angular, orV-shaped. The profile of the outer peripheral surface 1534 of theabrasive body 1530 of the abrasive article 1506 will be reproduced inreverse on the material to be shaped by the grinding wheel assembly1500.

The abrasive article 1506 of the present disclosure may be selected froma range of suitable sizes to facilitate efficient grinding dependingupon the workpiece. In one embodiment, the abrasive article 1506 caninclude a diameter of at least about 25 mm, such as at least about 30 mmor at least about 50 mm. In another embodiment, the diameter may be notgreater than 500 mm, such as not greater than 450 mm, not greater than300 mm or not greater than 200 mm. It will be appreciated that thediameter can be within a range between any of the minimum and maximumvalues noted above, such as from about 25 mm to about 500 mm, from about50 mm to about 250 mm, or from about 25 mm to about 150 mm.

The abrasive article 1306 of the present disclosure can be designed forshaping the edges of a workpiece. The workpiece can be an inorganic ororganic material, such as, for example, glass, plastic, ceramic, ormetal. In a particular embodiment, the workpiece can include glass,including but not limited to automotive glass, architectural glass,furniture glass, optical glass, and glass used in displays and/or tocover electronic devices (e.g., a phone). The workpiece can further becrystalline, such as monocrystalline or polycrystalline, including butnot limited to sapphire.

In a particular embodiment, the abrasive article 1306 of the presentdisclosure can be an abrasive wheel. In one aspect, the burst strengthof the abrasive wheel may be at least 135 m/s, such as at least 135 m/s,at least 160 m/s or at least 180 m/s. In another embodiment, the burststrength may be not larger than 300 m/s, such as not larger than 280m/s, or not larger than 250 m/s.

Cover Plate

FIG. 20 through FIG. 23 illustrate the details concerning theconstruction of the cover plate 1308. The cover plate 1308 can include abody 2000 that is generally disk-shaped. Further, the body 2000 of thecover plate 1308 can include an upper surface 2002 and a lower surface2004. The body 2000 of the cover plate 1308 can also include an outerwall 2006 extending between the upper surface 2002 and the lower surface2004. The lower surface 2004 and outer wall 2006 of the cover plate 1308are configured to be complimentary in size and shape to the recessedsurface 1514 and the sidewall 1516 of the core 1500 of the abrasivearticle 1306. As depicted in FIG. 24, this shape allows the cover plate1308 to fit into the upper recessed portion 1510 of the core 1500 of theabrasive article 1306 and engage the recessed surface 1514 and thesidewall 1516. Specifically, the lower surface 2004 of the body 2000 ofthe cover plate 108 can abut and engage the recessed surface 1514 of theupper recessed portion 1510 of the core 1500 of the abrasive article1306. Moreover, the outer wall 2006 of the body 2000 of the cover plate1308 can abut and engage the sidewall 1516 of the core 1500 of theabrasive article 1306 the surrounds, or circumscribes, the recessedsurface 1514 of the upper recessed portion 1510 of the core 1500 of theabrasive article 1306. Accordingly, the upper recessed portion 1510 ofthe core 1500 of the abrasive article 1306 is sized and shaped toreceive the complimentary sized and shaped cover plate 1308 therein.Further, the cover plate 1308 fits into the upper recessed portion 1510of the upper surface 1502 of the core 1500 of the abrasive article 1306,so that the upper surface 2002 of the cover plate 1308, i.e., the body2000 of the cover plate 1308, is substantially coplanar with the uppersurface 1502 of the core 1500 of the abrasive article 1306.

As illustrated in FIG. 22 and FIG. 23, a generally cylindrical hub 2008can extend outwardly from the lower surface 2004 of the body 2000 of thecover plate 1308 along a central axis 2010. The cylindrical hub 2008 isconfigured to extend into the central bore 1518 of the core 1500 of theabrasive article 1306 when the cover plate 1308 is fitted into the upperrecessed portion 1510 of the core 1500 of the abrasive article 1306.Moreover, FIG. 24 shows that the central bore 1518 of the core 1500 ofthe abrasive article 1306 can have a bore depth, D_(B), and the coverplate 1308, i.e., the cylindrical hug 2008 of the body 2000 of the coverplate 1308, can extend at least partially into the central bore 1518 ata depth, D_(E), and D_(E) can be less than or equal to 50% D_(B). Inanother aspect, D_(E) can be less than or equal to 45% D_(B), such asless than or equal to 40% D_(B), less than or equal to 35% D_(B), lessthan or equal to 30% D_(B), less than or equal to 25% D_(B), less thanor equal to 20% D_(B), or less than or equal to 10% D_(B). In anotheraspect, D_(E) can be greater than or equal to 2.5% D_(B), such asgreater than or equal to 5% D_(B), greater than or equal to 7.5% D_(B),or greater than or equal to 10% D_(B). It is to be understood that D_(E)can be within a range between, and including, any of the maximum andminimum values of D_(E) described herein.

In a particular aspect, the cover plate 1308, i.e., the body 2000 of thecover plate 1308, has a diameter, D_(CP), and W_(RP) of the core 1500 ofthe abrasive article 1306 can be greater than or equal to 10% D_(CP).Moreover, W_(RP) can be greater than or equal to 12.5% D_(CP), such asgreater than or equal to 15% D_(CP), greater than or equal to 17.5%D_(CP), or greater than or equal to 20% D_(CP). In another aspect,W_(RP) can be less than or equal to 30.0% D_(CP), such as less than orequal to 27.5% D_(CP), less than or equal to 25% D_(CP), or less than orequal to 22.5% D_(CP). It is to be understood that W_(RP) can be withina range between and including any of the maximum and minimum % D_(CP)values described herein.

In still another aspect, the upper recessed portion 1510, or therecessed surface 1514 of the upper recessed portion 1510, can have asurface area, A_(RP). Further, the cover plate 1510, e.g., the uppersurface 1502 of the body 1500 of the cover plate, can have a surfacearea, A_(CP), and A_(RP) can less than or equal to 75.0% A_(CP). Inanother aspect, A_(RP) can be less than or equal to 72.5% A_(CP), suchas less than or equal to 70.0% A_(CP), less than or equal to 67.5%A_(CP), less than or equal to 65.0% A_(CP), less than or equal to 62.5%A_(CP), less than or equal to 60.0% A_(CP), or less than or equal to57.5% A_(CP). In yet another aspect, A_(RP) can be greater than or equalto 40.0% A_(CP), such as greater than or equal to 42.5% A_(CP), greaterthan or equal to 45.0% A_(CP), greater than or equal to 47.5% A_(CP),greater than or equal to 50.0% A_(CP), greater than or equal to 52.5%A_(CP), or greater than or equal to 55.0% A_(CP). It is to be understoodthat A_(RP) can be within a range between and including any of themaximum and minimum % A_(CP) values described herein.

In another aspect, the core 1500 of the abrasive article 1306 can havean internal volume, V_(C), that is the combined volume of the upperrecessed portion 1510 of the core 1500 of the abrasive article 1306 andthe central bore 1518 of the core 1500 of the abrasive article 1306. Itis to be understood that V_(C) is the volume within the core 1500 of theabrasive article 1306, i.e., between the upper surface 1502 of the core1500 and the lower surface 1504 of the core 1500, that is bound by thesidewall 1516 of the upper recessed portion 1510 of the core 1500, therecessed surface 1514 of the upper recessed portion 1510 of the core1500, and the inner wall 1520 of the core 1500. Further, a displacedvolume, V_(D), which is the volume displaced, or filled, by the body2000 of the cover plate 1308 when the cover plate 1308 is installedwithin the abrasive article 1306, e.g. within the upper recessed portion1510 and the central bore 1518 of the core 1500, can be greater than orequal to 60.0% V_(C). In another aspect, V_(D) can be greater than orequal to 62.5% V_(C), such as greater than or equal to 65.0% V_(C),greater than or equal to 67.5% V_(C), greater than or equal to 70.0%V_(C), greater than or equal to 72.5% V_(C), greater than or equal to75.0% V_(C), greater than or equal to 77.5% V_(C), greater than or equalto 80.0% V_(C), or greater than or equal to 82.5% V_(C). In anotheraspect, V_(D) can be less than or equal to 100.0% V_(C), such as lessthan or equal to 97.5% V_(C), less than or equal to 95.0% V_(C), lessthan or equal to 92.5% V_(C), less than or equal to 90.0% V_(C), lessthan or equal to 87.5% V_(C), or less than or equal to 85.0% V_(C). Itis to be understood that V_(D) can be within a range between, andincluding, any of the minimum and maximum values of V_(D) describedherein.

As shown in FIG. 20, FIG. 21, FIG. 23, and FIG. 24, the body 2000 of thecover plate 1308 can include at least one bore 2012 extending throughthe cover plate 1308, i.e., between the upper surface 2002 and the lowersurface 2004. The at least one bore 2012 can be radially offset from thecentral axis 2010. The at least one bore 2012 can be a smooth walledbore and may be sized and shaped to allow the at least one fastener1510, shown in FIG. 15, to extend through the at least one bore 2012 andengage the at least one bore 2012 in a slip fit arrangement. Further,the body 2000 of the cover plate 1308 can include at least one generallysemi-circular cutout 2014 that can be aligned with a manufacturing hole1532 on the core 1500 of the abrasive article 1306 when the cover plate1308 is installed within the abrasive article 1306 as shown in FIG. 24.

In a particular embodiment, the cover plate 1308 can be made from ametal, a metal alloy, or a combination thereof. Further, the cover plate1308 can be from a non-ferrous metal. For example, the cover plate 1308can be made from aluminum, an aluminum alloy, or a combination thereof.Moreover, the cover plate 1308 can be made from copper, brass, or acombination thereof. Further still, the cover plate 1308 can be madefrom tin, bronze, or a combination thereof.

It is to be understood that the configuration of structure describedherein provides a grinding wheel assembly that substantially minimizesthe splashing of cutting fluid, or coolant, on a workpiece during anedge grinding operation. This substantially minimizes swarf and debrisfrom collecting on the workpiece and potentially causing scratches orother damage to the workpiece. Specifically, the manner in which thecover plate fits into the abrasive article and forms an enclosed surfaceat the top of the grinding wheel assembly can substantially minimize thesplashing of coolant and swarf. Further, the shape of the cover platerelative to the upper recessed portion of the abrasive article, e.g.,the complimentary shape of the lower surface of the cover plate withrespect to the recessed surface, provides a structure that evenlydistributes the compressive forces on the recessed surface of theabrasive article from the threaded fasteners when the grinding wheelassembly is properly assembled. This distribution of the compressiveforces substantially minimizes, or eliminates, the cracking, orbreaking, of the polymeric core of the abrasive article during assemblyof the grinding wheel assembly. Moreover, the close fit of the coverplate within the upper recessed portion of the abrasive article cansubstantially minimize vibration of the abrasive article during edgegrinding operations.

Many different aspects and embodiments are possible. Some of thoseaspects and embodiments are described herein. After reading thisspecification, skilled artisans will appreciate that those aspects andembodiments are only illustrative and do not limit the scope of thepresent invention. Embodiments may be in accordance with any one or moreof the items as listed below.

EMBODIMENTS Embodiment 1

An abrasive article, comprising:

a core comprising a polymer material, the core having an upper surface,an outer peripheral surface, an upper recessed portion extending intothe core from the upper surface and a peripheral recess extending intothe outer peripheral surface;

a bonded abrasive body disposed within the peripheral recess of theouter peripheral surface of the core; and

a cover plate having an upper surface, wherein the cover plate fits intothe upper recessed portion of the upper surface the core so that theupper surface of the cover plate is substantially coplanar with theupper surface of the core.

Embodiment 2

An abrasive article, comprising:

a core, the core having an upper surface, an outer peripheral surface,an upper recessed portion extending into the core from the upper surfaceand an peripheral recess extending into the outer peripheral surface,wherein the upper recessed portion includes a recessed surface;

a bonded abrasive body disposed within the peripheral recess of theouter peripheral surface of the core; and

a cover plate, wherein the cover plate fits entirely within the upperrecessed portion of the core and mates with the recessed surface.

Embodiment 3

An abrasive article, comprising:

a core, the core having an upper surface, an outer peripheral surface,an upper recessed portion extending into the core from the upper surfaceand a peripheral recess extending into the outer peripheral surface,wherein the upper recessed portion is sized and shaped to receive acomplimentary sized and shaped cover plate therein; and

a bonded abrasive body disposed within the peripheral recess of theouter peripheral surface of the core.

Embodiment 4

The abrasive article of any of embodiments 1, 2, or 3, wherein the corefurther comprises a central bore and the cover plate extends at leastpartially into the central bore.

Embodiment 5

The abrasive article according to embodiment 4, wherein the bore has adepth, D_(B), and the cover plate extends into the bore at a depth,D_(E), and D_(E) is less than or equal to 50% D_(B).

Embodiment 6

The abrasive article according to embodiment 5, wherein D_(E) is lessthan or equal to 45% D_(B), such as less than or equal to 40% D_(B),less than or equal to 35% D_(B), less than or equal to 30% D_(B), lessthan or equal to 25% D_(B), less than or equal to 20% D_(B), or lessthan or equal to 15% D_(B).

Embodiment 7

The abrasive article according to embodiment 6, wherein D_(E) is greaterthan or equal to 2.5% D_(B), such as greater than or equal to 5% D_(B),greater than or equal to 7.5% D_(B), or greater than or equal to 10%D_(B).

Embodiment 8

The abrasive article according to any of embodiments 1, 2, or 3, whereinthe recessed portion has a radial width, W_(RP), and the core has aradial width, W_(C), and W_(RP) is greater than or equal to 40% W_(C).

Embodiment 9

The abrasive article according to embodiment 8, wherein W_(RP) isgreater than or equal to 45% W_(C), such as greater than or equal to 50%W_(C), or greater than or equal to 55% W_(C).

Embodiment 10

The abrasive article according to embodiment 9, wherein W_(RP) is lessthan or equal to 75% W_(C), such as less than or equal to 70% W_(C),less than or equal to 65% W_(C), or less than or equal to 60% W_(C).

Embodiment 11

The abrasive article according to any of embodiments 1, 2, or 3 whereinthe recessed portion has a radial width, W_(RP), and the cover plate hasa diameter, D_(CP), and W_(RP) is greater than or equal to 10% D_(CP).

Embodiment 12

The abrasive article according to embodiment 11, wherein W_(RP) isgreater than or equal to 12.5% D_(CP), such as greater than or equal to15% D_(CP), greater than or equal to 17.5% D_(CP), or greater than orequal to 20% D_(CP).

Embodiment 13

The abrasive article according to embodiment 12, wherein W_(RP) is lessthan or equal to 30.0% D_(CP), such as less than or equal to 27.5%D_(CP), less than or equal to 25% D_(CP), or less than or equal to 22.5%D_(CP).

Embodiment 14

The abrasive article according to any of embodiments 1, 2, or 3, whereinthe recessed portion has a recessed surface formed at an angle, a, withrespect to the upper surface and a is greater than or equal to 5°.

Embodiment 15

The abrasive article according to embodiment 14, wherein a is greaterthan or equal to 7.5°, such as greater than or equal to 10°, greaterthan or equal to 12.5°, or greater than or equal to 15°.

Embodiment 16

The abrasive article according to embodiment 15, wherein a is less thanor equal to 30°, such as less than or equal to 27.5°, less than or equalto 25°, less than or equal to 22.5°, or less than or equal to 22°.

Embodiment 17

The abrasive article according to any of embodiments 1, 2, or 3, whereinthe recessed portion has a surface area, A_(RP), and the cover plate hasa surface area, A_(CP), and A_(RP) is less than or equal to 75.0%A_(CP).

Embodiment 18

The abrasive article according to embodiment 17, wherein A_(RP) is lessthan or equal to 72.5% A_(CP), such as less than or equal to 70.0%A_(CP), less than or equal to 67.5% A_(CP), less than or equal to 65.0%A_(CP), less than or equal to 62.5% A_(CP), less than or equal to 60.0%A_(CP), or less than or equal to 57.5% A_(CP).

Embodiment 19

The abrasive article according to embodiment 18, wherein A_(RP) isgreater than or equal to 40.0% A_(CP), such as greater than or equal to42.5% A_(CP), greater than or equal to 45.0% A_(CP), greater than orequal to 47.5% A_(CP), greater than or equal to 50.0% A_(CP), greaterthan or equal to 52.5% A_(CP), or greater than or equal to 55.0% A_(CP).

Embodiment 20

The abrasive article according to any of embodiments 1, 2, or 3, whereinthe cover plate is made from a metal, a metal alloy, or a combinationthereof.

Embodiment 21

The abrasive article according to embodiment 20, wherein the cover plateis made from non-ferrous metal.

Embodiment 22

The abrasive article according to embodiment 21, wherein the cover plateis made from aluminum, an aluminum alloy, or a combination thereof.

Embodiment 23

The abrasive article according to embodiment 21, wherein the cover plateis made from copper, brass, or a combination thereof.

Embodiment 24

The abrasive article according to embodiment 23, wherein the cover plateis made from tin, bronze, or a combination thereof.

Embodiment 25

The abrasive article according to any of embodiments 1, 2, or 3, whereinno part of the abrasive article extends above the upper surface of thecore.

Embodiment 26

The abrasive article according to any of embodiments 1, 2, or 3, whereinno part of the abrasive article or the cover plate extends above theupper surface of the core.

Embodiment 27

The abrasive article according to any of embodiments 1, 2, or 3, whereinthe core comprises and an inner volume, V_(C); the cover plate candisplace a volume, V_(D), when the cover plate is installed within thecore; and V_(D) is greater than or equal to 60.0% V_(C).

Embodiment 28

The abrasive article according to embodiment 27, wherein V_(D) isgreater than or equal to 62.5% V_(C), such as greater than or equal to65.0% V_(C), greater than or equal to 67.5% V_(C), greater than or equalto 70.0% V_(C), greater than or equal to 72.5% V_(C), greater than orequal to 75.0% V_(C), greater than or equal to 77.5% V_(C), greater thanor equal to 80.0% V_(C), or greater than or equal to 82.5% V_(C).

Embodiment 29

The abrasive article according to embodiment 28, wherein V_(D) is lessthan or equal to 100.0% V_(C), such as less than or equal to 97.5%V_(C), less than or equal to 95.0% V_(C), less than or equal to 92.5%V_(C), less than or equal to 90.0% V_(C), less than or equal to 87.5%V_(C), or less than or equal to 85.0% V_(C).

Embodiment 30

The abrasive article according to any of embodiments 1, 2, and 3,wherein the core comprises a polymer material.

Embodiment 31

The abrasive article according to embodiment 30, wherein the polymermaterial includes at least one of a polyamide (PA), a polybutyleneterephthalate (PBT), a polyphenylene sulfide (PPS), ethylenetetrafluoroethylene (ETFE), a polyetherketone (PEEK), a polyester (PE),a polyethyleneimine (PEI), a polyethersulfone (PESU), a polyethyleneterephthalate (PET), a polyphthalamide (PPA), a poly (p-phenylenesulfide), a polycarbonate (PC), an acrylonitrile-butadiene-styrene(ABS), a PC-ABS, or any combination thereof.

Embodiment 32

The abrasive article according to embodiment 30, wherein the corefurther comprises reinforcing fibers.

Embodiment 33

The abrasive article according to embodiment 32, wherein the reinforcingfibers include at least one of glass fibers, carbon fibers, ceramicfibers, organic fibers, mineral fibers, or any combination thereof.

The specification and illustrations of the embodiments described hereinare intended to provide a general understanding of the structure of thevarious embodiments. The specification and illustrations are notintended to serve as an exhaustive and comprehensive description of allof the elements and features of apparatus and systems that use thestructures or methods described herein. Separate embodiments may also beprovided in combination in a single embodiment, and conversely, variousfeatures that are, for brevity, described in the context of a singleembodiment, may also be provided separately or in any subcombination.Further, reference to values stated in ranges includes each and everyvalue within that range. Many other embodiments may be apparent toskilled artisans only after reading this specification. Otherembodiments may be used and derived from the disclosure, such that astructural substitution, logical substitution, or another change may bemade without departing from the scope of the disclosure. Accordingly,the disclosure is to be regarded as illustrative rather thanrestrictive. Benefits, other advantages, and solutions to problems havebeen described above with regard to specific embodiments. However, thebenefits, advantages, solutions to problems, and any feature(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature of any or all the claims.

The description in combination with the figures is provided to assist inunderstanding the teachings disclosed herein. The following discussionwill focus on specific implementations and embodiments of the teachings.This focus is provided to assist in describing the teachings and shouldnot be interpreted as a limitation on the scope or applicability of theteachings. However, other teachings can certainly be used in thisapplication.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a method,article, or apparatus that comprises a list of features is notnecessarily limited only to those features but may include otherfeatures not expressly listed or inherent to such method, article, orapparatus. Further, unless expressly stated to the contrary, “or” refersto an inclusive-or and not to an exclusive-or. For example, a conditionA or B is satisfied by any one of the following: A is true (or present)and B is false (or not present), A is false (or not present) and B istrue (or present), and both A and B are true (or present).

Also, the use of “a” or “an” is employed to describe elements andcomponents described herein. This is done merely for convenience and togive a general sense of the scope of the invention. This descriptionshould be read to include one or at least one and the singular alsoincludes the plural, or vice versa, unless it is clear that it is meantotherwise. For example, when a single item is described herein, morethan one item may be used in place of a single item. Similarly, wheremore than one item is described herein, a single item may be substitutedfor that more than one item.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples are illustrative only and not intended to be limiting. To theextent not described herein, many details regarding specific materialsand processing acts are conventional and may be found in reference booksand other sources within the structural arts and correspondingmanufacturing arts.

The above-disclosed subject matter is to be considered illustrative, andnot restrictive, and the appended claims are intended to cover all suchmodifications, enhancements, and other embodiments, which fall withinthe true scope of the present invention. Thus, to the maximum extentallowed by law, the scope of the present invention is to be determinedby the broadest permissible interpretation of the following claims andtheir equivalents, and shall not be restricted or limited by theforegoing detailed description.

What is claimed is:
 1. An abrasive article, comprising: a corecomprising a polymer material, the core having an upper surface, anouter peripheral surface, an upper recessed portion extending into thecore from the upper surface and a peripheral recess extending into theouter peripheral surface; a bonded abrasive body disposed within theperipheral recess of the outer peripheral surface of the core; and acover plate having an upper surface, wherein the cover plate fits intothe upper recessed portion of the upper surface the core so that theupper surface of the cover plate is substantially coplanar with theupper surface of the core.
 2. The abrasive article of claim 1, whereinthe core further comprises a central bore and the cover plate extends atleast partially into the central bore.
 3. The abrasive article of claim2, wherein the bore has a depth, D_(B), and the cover plate extends intothe bore at a depth, D_(E), and D_(E) is less than or equal to 50%D_(B).
 4. The abrasive article of claim 3, wherein D_(E) is greater thanor equal to 2.5% D_(B), such as greater than or equal to 5% D_(B),greater than or equal to 7.5% D_(B), or greater than or equal to 10%D_(B).
 5. The abrasive article of claim 1, wherein the recessed portionhas a radial width, W_(RP), and the core has a radial width, W_(C), andW_(RP) is greater than or equal to 40% W_(C).
 6. The abrasive article ofclaim 5, wherein W_(RP) is less than or equal to 75% W_(C), such as lessthan or equal to 70% W_(C), less than or equal to 65% W_(C), or lessthan or equal to 60% W_(C).
 7. The abrasive article of claim 1, whereinthe recessed portion has a radial width, W_(RP), and the cover plate hasa diameter, D_(CP), and W_(RP) is greater than or equal to 10% D_(CP).8. The abrasive article of claim 7, wherein W_(RP) is less than or equalto 30.0% D_(CP), such as less than or equal to 27.5% D_(CP), less thanor equal to 25% D_(CP), or less than or equal to 22.5% D_(CP).
 9. Anabrasive article, comprising: a core, the core having an upper surface,an outer peripheral surface, an upper recessed portion extending intothe core from the upper surface and an peripheral recess extending intothe outer peripheral surface, wherein the upper recessed portionincludes a recessed surface; a bonded abrasive body disposed within theperipheral recess of the outer peripheral surface of the core; and acover plate, wherein the cover plate fits entirely within the upperrecessed portion of the core and mates with the recessed surface. 10.The abrasive article of claim 9, wherein the recessed portion has arecessed surface formed at an angle, a, with respect to the uppersurface and a is greater than or equal to 5°.
 11. The abrasive articleof claim 10, wherein a is less than or equal to 30°, such as less thanor equal to 27.5°, less than or equal to 25°, less than or equal to22.5°, or less than or equal to 22°.
 12. The abrasive article of claim9, wherein the recessed portion has a surface area, A_(RP), and thecover plate has a surface area, A_(CP), and A_(RP) is less than or equalto 75.0% A_(CP).
 13. The abrasive article of claim 12, wherein A_(RP) isgreater than or equal to 40.0% A_(CP), such as greater than or equal to42.5% A_(CP), greater than or equal to 45.0% A_(CP), greater than orequal to 47.5% A_(CP), greater than or equal to 50.0% A_(CP), greaterthan or equal to 52.5% A_(CP), or greater than or equal to 55.0% A_(CP).14. An abrasive article, comprising: a core, the core having an uppersurface, an outer peripheral surface, an upper recessed portionextending into the core from the upper surface and a peripheral recessextending into the outer peripheral surface, wherein the upper recessedportion is sized and shaped to receive a complimentary sized and shapedcover plate therein; and a bonded abrasive body disposed within theperipheral recess of the outer peripheral surface of the core.
 15. Theabrasive article of claim 14, wherein the cover plate is made from ametal, a metal alloy, or a combination thereof.
 16. The abrasive articleof claim 15, wherein the cover plate is made from non-ferrous metal. 17.The abrasive article of claim 14, wherein no part of the abrasivearticle extends above the upper surface of the core.
 18. The abrasivearticle of claim 14, wherein no part of the abrasive article or thecover plate extends above the upper surface of the core.
 19. Theabrasive article of claim 14, wherein the core comprises and an innervolume, V_(C); the cover plate can displace a volume, V_(D), when thecover plate is installed within the core; and V_(D) is greater than orequal to 60.0% V_(C).
 20. The abrasive article of claim 19, whereinV_(D) is less than or equal to 100.0% V_(C), such as less than or equalto 97.5% V_(C), less than or equal to 95.0% V_(C), less than or equal to92.5% V_(C), less than or equal to 90.0% V_(C), less than or equal to87.5% V_(C), or less than or equal to 85.0% V_(C).